1. Field of the Invention
The present invention relates to improvements in tamper-evidencing closures including tamper-evidencing bands such as those commonly used as bottle caps. In particular, the present invention relates to an improved detachable tamper-evidencing band design for improved mounting of the closure on a spout or neck of a container, as well as to improve the engagement of the tamper-evidencing band with the spout or neck and improve the drainage of spilled product and/or wash water from the closure.
2. Description of Related Art
U.S. Pat. No. 4,801,031 to Barriac discloses a tamper-indicating closure that includes an inwardly folded tamper-indicating band with intermittent pleats, around the inwardly folded portion of the band. The pleats are inwardly directed and spaced around the circumference of the band. U.S. Pat. No. 5,400,913 to Kelly discloses a similar tamper-indicating closure that also has an inwardly folded tamper-indicating band with continuous pleats around the inwardly folded portion of the band.
As discussed in the Kelly ""913 patent, the tamper-indicating band should slip over the locking bead or rim of the container neck without damaging the frangible connection between the band and the skirt of the closure. The tamper-indicating band must be sufficiently elastic in order to avoid too great a resistance when closing the bottle, which could damage the frangible connection. However, the tamper-indicating band should be sufficiently stiff in order to reliably engage the locking bead of the container neck and thereby hold the band beneath the locking bead when opening the closure, so that the tamper-indicating band will sever the frangible connection.
The Kelly ""913 patent improves the flexibility of the inwardly folded pleated portion of the band in two ways. One, a frangible connection is provided between each pleat. The frangible connections between the pleats ensure high elasticity of the tamper-indicating band during closure. Alternatively, individual bridges, instead of a frangible connection, are provided between the pleats. The bridges are relatively easily damaged during opening of the closure, thus improving the tamper-indicating nature of the closure.
It has been determined by the applicant herein that the inwardly-turned pleated designs of both the Barriac ""031 patent and the Kelly ""913 patent have a tendency to improperly grip the locking bead of the container neck and, thereby allow the tamper-indicating band to slip back upwardly over the locking bead upon opening of the closure, which defeats the tamper-indicating aspect of the designs. The present invention improves upon this aspect of prior art pleated tamper-indicating bands.
It is also known for the internal thread pattern of a bottle cap to include spaced gaps around the spiral thread bead for the purpose of reducing weight of the bottle cap as well as to simplify tooling production required to manufacture the bottle caps. The present invention also provides an improved spiral thread pattern and design.
A further problem encountered with tamper-evidence closures is that the tamper-indicating band and inwardly turned retaining rim can trap liquid in the closure. Thus, product used to fill the container can spill on the container neck and when the container is closed by the closure or cap, the liquid product trapped by the inwardly turned retaining rim. Similarly, in many instances the container will be washed after capping, and the wash water can become trapped in the cap. In either case, and particularly for products which contain sugar, the trapped liquid can act as a habitat for the growth of bacteria, mold and the like.
Briefly described, the present invention comprises a tamper-evidencing closure for a container with a locking surface on the neck of the container, with the closure including a closure or cap with a top portion and a depending annular skirt, a tamper-evidencing band connected to the lower edge of the annular skirt by means of a frangible connection, the tamper-evidencing band including an inwardly turned retaining rim that extends at least partially upwardly relative to the container neck, the retaining rim including a free edge that is adapted to engage the locking surface of the container neck. Optionally, the retaining rim includes ramp elements that provide for one-way screwing of the closure cap onto a neck having corresponding ramp elements.
One aspect of the present invention is directed to a container including a neck and an opening, in combination with a tamper-evidencing closure including a top, a depending annular skirt and a tamper-evidencing band frangibly connected to the annular skirt. The container includes a locking surface on the neck spaced from the opening. The tamper-evidencing band includes an inwardly turned retaining rim that extends at least partially upwardly. The retaining rim has a free edge having a locking surface engaging structure formed for engagement with the locking surface as the closure is removed from the neck to ensure breakage of the frangible connection. The locking surface engaging structure can include a plurality of outwardly directed flutes spaced circumferentially thereon and a second securing structure located on the retaining rim between the flutes.
In another aspect of the present invention the inwardly turned retaining rim with the locking surface engaging structure is further formed with at least one, and preferably a plurality, of passageways therethrough which allow for the drainage and/or evaporation of liquid trapped by the closure. The provision of one passageway between each pair of circumferentially adjacent locking surface engaging flutes is particularly advantageous.
The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.